CVE-2026-28899

Gatekeeper Bypass Allowing Unsigned Code Execution in macOS

Published Sep 14, 2026 CVSS 3.1 · 5.5 Medium EPSS < 1% KEV · Not listed
Description
A logic issue was addressed with improved checks. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.6, macOS Tahoe 26.7. An app may bypass Gatekeeper checks.

Analysis

AI-generated

Technical impact

The vulnerability is a logic defect in macOS’s Gatekeeper system that enables an application to bypass built‑in code‑signing checks. When an unsigned or malicious package is allowed to run, it can execute with the privileges of the installing user, potentially compromising confidentiality, integrity, and availability. The weakness is an instance of improper access control, as it permits execution that Gatekeeper is explicitly designed to prohibit.

Affected Systems

Apple macOS releases affected are macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.6 and 26.7. Earlier or later releases are considered unaffected unless Apple explicitly notes otherwise.

Risk and Exploitability

An EPSS score of less than 1% indicates a very low, but non‑zero, likelihood of exploitation. The vulnerability is not listed in the CISA KEV catalog, meaning no known active exploits are reported. The likely attack vector is local: a user who installs a package that has circumvented Gatekeeper checks, either through user interaction or by exploiting a configuration that permits unsigned applications. While the overall exploitation probability remains low in a well‑secured environment, the impact of a successful bypass is high, so timely patching is strongly advised.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Install the macOS update that includes the Gatekeeper bypass fix (macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.6/26.7 or newer).
  • Ensure Gatekeeper is enabled in System Settings → Security & Privacy → General, selecting only App Store or signed developers as allowed sources.
  • If an OS update cannot be applied, configure Gatekeeper to block unknown developers and educate users to avoid running software from unverified sources.

Generated by OpenCVE AI on September 20, 2026 at 20:04 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Title Gatekeeper Bypass Allowing Unsigned Code Execution in macOS
Type Values Removed Values Added
CPEs cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
Type Values Removed Values Added
Weaknesses CWE-693
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Gatekeeper Bypass Allowing Unsigned Application Execution
Weaknesses CWE-285
Type Values Removed Values Added
Title Gatekeeper Bypass Allowing Unsigned Application Execution
Weaknesses CWE-285
Type Values Removed Values Added
First Time appeared Apple
Apple macos
Vendors & Products Apple
Apple macos
Type Values Removed Values Added
Description A logic issue was addressed with improved checks. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.6, macOS Tahoe 26.7. An app may bypass Gatekeeper checks.
References
Weaknesses
  • CWE-693

    Protection Mechanism Failure

Sources

Status
PUBLISHED
Assigner
apple
Published
Updated
Oct 26, 2026, 8:37 PM
Reserved
Mar 3, 2026, 4:36 PM
Status
Analyzed
Published
Sep 14, 2026, 9:17 PM
Modified
Sep 17, 2026, 6:40 PM